The described subject matter relates generally to the field of additive manufacturing. In particular, the subject matter relates to operating an energy beam to facilitate additive manufacturing.
Additive manufacturing refers to a category of manufacturing methods characterized by the fact that the finished part is created by layer-wise construction of a plurality of thin sheets of material. Additive manufacturing may involve applying liquid or powder material to a workstage, then doing some combination of sintering, curing, melting, and/or cutting to create a layer. The process is repeated up to several thousand times to construct the desired finished component or article.
Various types of additive manufacturing are known. Examples include stereo lithography (additively manufacturing objects from layers of a cured photosensitive liquid), electron beam melting (using a powder as feedstock and selectively melting the powder using an electron beam), laser additive manufacturing (using a powder as a feedstock and selectively melting the powder using a laser), and laser object manufacturing (applying thin solid sheets of material over a workstage and using a laser to cut away unwanted portions).
Many additive manufacturing processes utilize a scanning energy beam to fuse a fusible material. Scanning is commonly implemented in a raster scanning mode where a plurality of substantially parallel scan lines are used to form the article. In order to reduce deformation of the layers from thermal or chemical reaction kinetics effects, each layer is often scanned in discrete sections at separate locations along the layer. Seams are thus formed at boundaries between adjacent sections. It is known to avoid direct stacking of seams between adjacent layers by providing some variation in section patterning between adjacent layers. However, such variation in section patterning has been practiced utilizing pre-set repeating variation patterns without regard to the specifics of the article being manufactured. Although such pre-set repeating patterns can reduce direct vertical seam stacking can still occurs through repetition of section patterning throughout the various layers of the manufactured article.